MOLLUSCA FROM JUAN FERNANDEZ AND EASTER ISLAND 24 1 



Feniandesia is perhaps to be considered as a secondary appearance, arisen by 

 means of reduction from a Torjiatcllina stage. 



PiLSBRY (191 1, Man. of Conch., Vol. 21) has described some new species 

 of the genus. Only three of the previously known ones were collected by the 

 Swedish expedition; to these comes one new, the smallest hitherto known, 

 remarkable for its polygyrate shell. The second species, with its strikingly small 

 aperture, proves to agree with F. tryoni (PiLSBRY, pi. 14, fig. 12), the third, 

 and largest species, corresponds to F. bulimoides Reeve (incl. consimilis Reeve, 

 which seems merely to be the narrow variety), as well as to Pfeiffer's figure 

 of F. splendida in the Conchylien Cabinet (cf. PiLSBRY, pi. 14, fig. 10). The 

 fourth species corresponds well to the figure of F. splendida Anton, given by 

 Reeve (Conch. Icon. V, f. icxd) and, though less exactly, to that given by 

 PFEIFFER in 1847 (cf. PiLSBRY, pi. 1 4, f. 9). 



The difference between the two last-named forms is involved in the rapidly 

 increasing whorls of the former (bulimoides) which render the shell, at least in 

 young specimens, a convex outline, a globose shape and a relatively large 

 aperture (about half the height of the .shell), whereas F. splendida has the 

 whorls more slowly increasing by which the spire grows more produced and 

 straight and the aperture smaller (less than half the shell height). The difference 

 is most obvious in young shells, which differ considerably in size; a stage of 

 4 whorls measures in height 3,2 mm in splendida, and 5,1 in bulimoides. The 

 adult stage with 5 ^/2 whorls measures, in the former, 7 mm in height, 3,8 mm 

 in breadth, in the latter 10 and 6 resp. The ratio height to breadth is, more- 

 over, as variable as in Tornatellina, a feature common to all species of the genus. 



Fernandezia bulimoides Pfeiffer. PI. 9, fig. 47. — Masatierra, Aug. 1917: 

 Rabanal, down in the quebrada, under leaves, numerous empty shells, and some 

 living sps., max. h. 10; wh. 5, and about 300 m above sea, 2 small shs. — 

 Puerto Ingles, about 200 m, among leaves, i small sp., and about 400 m, thick 

 forest, some fragments and small sps. — Round Portezuelo, 570 m, on ferns, 

 some young shs. — The Portezuelo quebrada, up to 200 m, among leaves and 

 on ferns, some young sps. — Centinela Ridge, about 500 m, under leaves and 

 on ferns, 10 shs., h. about 10, and about 650 m, under ferns, i fragment. — 

 Masatierra, Vi 1917, on ferns, .some young sps.; V4 1917, about 500 m, shaken 

 down from bushes, 8 sps., max. h. 10,5; ^^U^ i small sp., among leaves; ^*/i2 



1916, some small sps. — Beneath Damajuana, about 300 m, thick forest, among 

 leaves, 3 shs., max. h. 10,5, fig. 47. 



Fernandezia splendida Anton. PI. 9, fig. 48. — Masatierra, Jan. -^ April 



1917, many sps., max. h, 6, wh. 5^/2 — 6; Aug. 1917: about 500 m above sea, 

 shaken down from bushes, some small sps., together with F. bulimoides. — 

 Salsipuedes Ridge, about 350 m, on ferns and beneath leaves, many sps., max. h. 

 about 6,8, wh. 5 ^U, fig- 48. — Piedra Agujeriada Valley, i small sh. — The 

 Portezuelo quebrada, up to 200 m, among leaves and on ferns, 3 shs., max. h. 6,4, 

 wh. 5. — Round Portezuelo, 570 m, on ferns, 4 shs., max. h. 5,3. — Pangal, 

 on ferns and under leaves, i sp., h. 6,35. — Below Damajuana, in thick forest, 

 about 300 m, 2 shs., max. h. 3,5. 



16 — S1197. The Nat. Hist, of Juan Fernandez and Easter Isl. Vol. III. 



